The present invention relates to a scanning electron microscope which irradiates a specimen with an electron beam and detects secondary electrons generated by irradiation of the specimen, and in particular, it relates to a scanning electron microscope which can detect secondary electrons in a designated energy region of the secondary electrons from the specimen.
The scanning electron microscope is generally comprised of the steps: irradiating a sample with an electron beam, detecting secondary electrons having been generated by irradiation of the sample using a secondary electron detector, and producing an image of the sample on the basis of a detection signal output therefrom.
The secondary electrons obtainable from the sample have a relatively broad energy region. Normally, all of these secondary electrons in the relatively broad energy region are output without selection of energy.